Assighobs to the abbott labobatobies



Patented Jan. 2, 1923. i l

F l C ROGER ADAMS, OF URBANA, AND ERNEST H. VOLWILER, OF CHICAGO, ILLINOIS,

ASSIGNORS TO THE ABBOTT LABORATORIES, OF CHICAGO, ILLINOIS, A CORPO- RATION OF ILLINOIS. v

N-BUTYL ESTERS OF PARA-AMINO BENZOIC ACID.

No Drawing. i Application filed March 19, 1920. Serial No. 367,228.

To all whom it may concern: concentrated sulfuric acid, are refluxed for Be it known that we, Rocnn AnAus and eight hours. The reaction mixture is then 50 ERNnsT H. VoLwILER, residing, respectively, vacuum-distilled in order to recover the exat Urbana, in the county of Champaign and cess alcohol, residue treated with dilute so- State of Illinois, and at Chicago, in the dium carbonate solution, then extracted with county of Cook and State of Illinois, both ether, dried, and then distilled. After the citizens of the United States of America, ether has been removed, the residue is 55 have invented certain new and useful Imwarmed up to vacuum for some time to re--' provements in N-Butyl Esters of laramove the remainder of the n-butyl alcohol.

Amino BenzoicAcid, of which the following The residue consists of fairly pure n-butyl is a specification. ester of p-nitrobenzoic acid, which may be Our invention relates to improvements in crystallized from petroleum ether. It forms esters of aromatic acids, and has particular large white plates, melting point 35. reference to the n-butyl esters. 25 of the nitro ester just mentioned is The principal object of the invention is to mixed vith 100 g. of powerediron, and

' provide a compound of the class described hydrochloric acid is gradually added, the

which shall have more lasting anesthetic mixture bein kept at about during the properties than compounds hitherto prereduction. S t irring is carried on constantly pared. and the reaction continued until no more I ester remains. The reaction mixture is then The f/enemz f filtered from the excess iron, made alkaline Pom! 8 of 28867168 with sodium hydroxide and extracted'with The nitro derivatives of n-butyl esters of ether. The ether solution upon evaporation aromatic acids are treated with iron powder yields the n-butyl ester of p-amino benzoic 25 and hydrochloric acid, keeping thetemperaacid, which may be' crystallized from water ture of the mixture at 50 and continuing or petroleum ether. It has a-melting point, the reaction until all the nitro compound is when pure, of 57-58%". dissolvetlJ l l l' en a clear liquid results, the This material is an'anesthetic compound reaction'miiit'ure is carefully made neutral, which may be used locally, internally, for

30 or, if no hydroxyl group is present, alkaline, dusting on wounds, and for anesthetic purand the free amino compound extracted with poses in general, and its formula is as folother, Upon evaporation of the ether sohfilows: tion the amino compounds desired are 0 L tained. In order to produce a substituted (P) NH2G6H4OOOC4H9 (n) 35 amino derivative, the primary amino com- Another specific compound of this series is pound is treated with an alkyl halide under the normal butyl ester of 1.3.5 diamino benthe usual conditions. zoic acid, which is prepared as follows:

S d An excess of normal butyl alcohol is added pemfic compmm 8 m 867,266 to the acid chloride of 1.3.5. dinitro benzoic 40 A specific compound belonging to the genacid and refluxed for an hour. The excess eral series as above defined is the n-butyl of butyl alcohol is removed by distillation in ester of p-amino-benzoic acid. This is made vacuo and the normal buty ester of 1.3.5 by the reduction of the n-butyl ester of pdinitro benzoic acid solidifies upon coohng. nitro benzoic' acid. Since this latter com- This is reduced to the normal butyl ester 45 pound has not yet been described, a brief of 1.3.5 diamino benzolc acid with iron and mention of its method of preparation is hydrochloric acid and the product thus bgiven here. A mixture of 50 got p-nitro tained is a viscous liquid which does not benzoic acid, g. of butyl a1cohol, 8 cc. of solidify at room temperature.

We claim as our invention: 1. A new compound of the formula 15 where R is an amino aryl radic'le.

2. As a new article of manufacture, the n- 20 butyl ester of an amino benzoic acid.

3; As a new article of manufacture, the nbutyl ester of para-amino benzoic acid.

ROGER ADAMS. ERNEST H. V OLWILER. 

